The document discusses unit testing as a crucial method for enhancing the quality and reliability of software in component-based engineering. It outlines the benefits of manual and automated unit testing, including early bug detection and improved developer confidence, as well as various tools and methodologies such as test-driven development. The conclusion emphasizes the importance of selecting appropriate testing tools to effectively streamline the unit testing process.

1. International Journal of Trend in Scientific Research and Development (IJTSRD)
Volume: 3 | Issue: 2 | Jan-Feb 2019 Available Online: www.ijtsrd.com e-ISSN: 2456 - 6470
@ IJTSRD | Unique Reference Paper ID – IJTSRD21458 | Volume – 3 | Issue – 2 | Jan-Feb 2019 Page: 638
Unit Testing to Support Reusable for
Component-Based Software Engineering
Khin Moe Sam
University of Computer Studies, Thaton, Mon State; Myanmar
ABSTRACT
Unit testing is a practical approach to improve the quality and reliability of software. Unit testing is usually performed by
programmers and is the base for all other tests such as integration testing and system testing. Unit Testing can be done
manually (and/or) automatically. The automated unit tests are written by the developers after thecompletion of functionality
coding. The number of defects reduced when automated unit tests are written iteratively similar to test driven development.
This framework proved that significant portions of windows application can be automatically tested without manual
intervention. This reduces the manpower involved in testing each and every unit of the applicationandincreasesthe qualityof
the software product.
Keywords: Unit Testing, Automatic Unit Testing, And Test Driven Development.
1. INTRODUCTION
Unit Testing is a kind of white box testing where individual
units of software are tested. The intension of unit testing is
to check whether each and every unit (module)of asoftware
works as per the developer’s expectation. Unit Testing can
be done manually (and/or) automatically. UnitTestingfinds
the defects in each and every unit of the application at initial
level of testing. It increases the confidence levels of
developer by ensuring that their code is working correctly.
Unit Testing ensuresthat codeworkscorrectly andimproves
the quality, reliability and cost of the application software
development. We initially performed unit testing manually
where it was a time consuming task and hence we intend to
choose automation of unit testing. To automate unit testing,
it is necessary to write test scripts called unit tests. Once the
unit tests are available, it is easy to automatetheunittesting.
(1) The purpose is to validate that each unit of the software
performs as designed. A unit is the smallest testable part of
any software. It usually has one or a few inputs and usuallya
single output. A combination of the two or more tools can
serve to merge the best of both worlds. The result is notonly
the sum of both mechanisms, but the creation of a new
quality of testing tool with new functionalityemergingout of
the combination of the two.(3)
2. Objectives
The goal of unit testing is to isolate each part of the program
and show that the individual parts are correct. (4)A
combination of the two can serve to merge the best of both
worlds. The result is not only the sum of both mechanisms,
but the creation of a new quality of testing tool with new
functionality emerging out of the combination of the two.
(3)(5)Unit testing is performed on thesmallestelementsof a
system; each component is tested to ensure that it properly
works. Usually it performs a single cohesive function. The
goal of unit testing is to analyze each small part of the code
and test that is working correctly. (6) The purpose is to
validate that each unit of the software performs asdesigned.
A unit is the smallest testable part of any software. It usually
has one or a few inputs and usually a single output.
(2)Benefits of writing good unit tests or unit testing:- Unit
testing supplies plentiful benefits: finding software bugs
early, simplifying integration, providing a source of
documentation, and many others, which I am going to share
in more detail: Unit testing reduces the number of bugs in
the system and acceptance testing;Costof locating andfixing
bugs in unit testing is very less as they are captured in very
early phase; Automated tests can run as frequently as
required; Unit testing makes it easier to change and refactor
the code; Unit testing can improve code design, especially
with test-drivendevelopment;Overalldevelopmenttime can
be used for unit testing; Unit tests are a form of
documentation; Unit testing improves teamwork; Code
coverage can be measured.(7)
3. Methodology
Automated unit testing helps in improving quality,
decreasing costs and reducing time required for testing.
However, all this is possible only with use of appropriate
testing tool. Following are various parameters critical to
selection of appropriate tool: Minimum implementation
time: This is possible when users are already familiar with
technology (language, method of working, integration
constraints) used by the testing tool. Additionally, extensive
documentation and support available help in reducing
implementation time. Minimum ownership and running
costs: An open source tool which is freetoaccessmaybeless
efficient and have higher operating costs. On the other hand,
a commercial tool available may require initial investment
but due to its better features might make testing efficient
and cost effective in the long run. Flexibility: Everyprojectis
unique in a certain way and has its own peculiar needs.Thus
an efficient testing tool while offeringmostrequiredfeatures
should also provide option of code modification. Further for
swift debugging, the framework should make test code
readable. (8)
The automated unit tests for any application can be written
in two ways: Before code implementation; after code
implementation. If unit tests are written before any code
implementation then it is known as Test Driven
Development. If Unit tests are written after the code
implementation then it is known as Test after Development.
(9) The best unit testing tools are NUnit, TestNG, JUnit,
JMockit, Emma, Quilt, HtmlUnit. JUnit,TestNG,NUnitarefree

2. International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470
@ IJTSRD | Unique Reference Paper ID – IJTSRD21458 | Volume – 3 | Issue – 2 | Jan-Feb 2019 Page: 639
open source unit testing tools. Nunit is a unit testing
framework based on .net platform. It is free tool allows to
write test scripts manually but not automatically. Itworksin
the same way as JUnit works for Java.
It supports data-driven tests that can run in parallel. It uses
console runner to load and execute tests. JUnit is an open-
source unit testing framework designed for Java
Programming language. It supports for test-driven
environment and the core idea on which it is based ‘first
testing then coding’. Test data is first tested and then
inserted in the piece of code. It provides annotation for test
method identification, assertion for testing expected result
and test runners. It is simplest and helps to write code easily
and faster. TestNG is an open-source automation testing
framework for java programming language. This tool is
heavily influenced by JUint and NUnit with concurrent
testing annotation support. TestNG supports parameterized
and data-driven testing along with unit functional and
integration testing. It proved effective with powerful
execution model and flexible test configuration.
4. Proposed System
In Test Driven Development, the developer writes
automated unit tests for the newfunctionalitythey areabout
to implement. It is a software engineering process that
follows small development cycle. In industry, while coding a
software application the development cycle that they follow
is shown below in figure 1.
Fig.1. Test Driven Development Cycle
4.1 Develop Automated Unit Tests
Without writing any code to implement feature, test cases
must be written by the developer in the initial stage by
collecting the specifications and requirements in theform of
user stories (or) use cases that covers all the requirements
and conditions. This makes developer to focus on
requirements and coding in this manner makes the code
consistent.
4.2 Run Automated Unit Tests
Run the automated Unit tests to ensurethattheyfailbecause
there is no implemented code yet.
4.3 Implement the Code to Pass Test(s)
Developer needs to write the code for those cases that are
failed in the previous test. The code that developer writes
should not add any other unpredicted functionality.
4.4 Run All the Tests in Code Base
Once development is done, run all the automated testsinthe
code base. If all the tests are passingthendevelop automated
unit tests for other features of the application and repeatthe
same process otherwise implement the code necessary to
make the test pass and run the automated unit test(s).
Finally, once the development of codeforthe applicationand
unit testing are done, the developer may restructure the
code for better readability (or) improving the performance.
The advantage of above written unit tests is that whatever
changes the developer may make to the code now, it won’t
affect the existing functionality of the build, as the test cases
written earlier defines the requirementand specifications of
the application.
5. Conclusion
Unit tests isolate each part of the program and checkthatthe
individual parts are correct. Unit testing finds problems
early in the development cycle and hence facilitates changes
required in code. Testing the parts of a program first and
then testing the sum, allows faster integration testing and
progressive documentation which are critical to the success
of the unit. However, considering the variety of testing tools
available and their variable features, it becomes essential
that features of each testing tool areanalyzedindetailbefore
any selection and use. As a future work direction, we plan to
apply mutation testing and analysis to the test suites
generative by our tool to assess their fault detection
effectiveness and to compare thateffectivenesswith those of
the test suites generated by other comparable tools. Wealso
plan to compare the effort and time spent in using those
tools. Also, the execution time of our tool to automatically
generate test case code is very fast, and we plan to compare
the associated efficiency to manual coding when our tool is
used in large-scale projects. (10)
References
[1] Aswatha Kumar M. et al. (Eds.): Proceedings of ICAdC,
AISC 174, pp. 813–822. springerlink.com ©
springer India 2013)
[2] Software testing fundamentals.com/ unit-
testing/(ISTQB)
[3] Andrew Patterson; Faculty of Information Technology;
Monash University; Australia; Introducing Unit Testing
With BlueJ,ajp@infotech. monash.edu.au

3. International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470
@ IJTSRD | Unique Reference Paper ID – IJTSRD21458 | Volume – 3 | Issue – 2 | Jan-Feb 2019 Page: 640
[4] Kolawa, Adam; Huizinga, Dorota (2007). Automated
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[5] johnr@infotech.monash.edu.au//
[6] https://apiumhub.com/tech-blog-barcelona/top-benefits-
of-unit-testing/
[7] By Ekaterina Novoseltseva; Jan. 18, 17 · DevOps Zone;
http://crestechglobal.com/the-importance-of-unit-
testing-in-software-testing/
[8] By Arvind Rongala,Manager, BusinessDevelopmentand
Marketing, Invensis Technologies) ;March 28, 2015
[9] A.N. Seshu Kumar and S. Vasavi; Effective Unit Testing
Framework for Automation of Windows Applications;
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{seshu1203, vasavi.movva} @gmail.com
[10] Christian Wiederseiner1, Shahnewaz A. Jolly1, Vahid
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